Radha walks 3 km 725 m per day on Monday, Wednesday and Friday, whereas she walks 2 km 9 m per day on Tuesday and Thursday. Total distance covered by her from Monday to Friday is :

The correct option is 15.193 km.

Let us calculate the total distance covered by Radha step-by-step from Monday to Friday.

Step 1: Convert distances into kilometers (km)

We know that 1 km = 1000 m, which means 1 m = 0.001 km.

Distance walked per day on Monday, Wednesday, and Friday:

$3 \mathrm{km}+725 m=3 \mathrm{km}+\frac{725}{1000} \mathrm{km}=3 \mathrm{km}+0.725 \mathrm{km}=3.725 \mathrm{km}$

Distance walked per day on Tuesday and Thursday:

$2 \mathrm{km}+9 m=2 \mathrm{km}+\frac{9}{1000} \mathrm{km}=2 \mathrm{km}+0.009 \mathrm{km}=2.009 \mathrm{km}$

Step 2: Calculate distance covered on specific sets of days

Number of days Radha walks 3.725 km (Monday, Wednesday, Friday) = 3 days.

Total distance for these 3 days:

$3\times 3.725 \mathrm{km}=11.175 \mathrm{km}$

Number of days Radha walks 2.009 km (Tuesday, Thursday) = 2 days.

Total distance for these 2 days:

$2\times 2.009 \mathrm{km}=4.018 \mathrm{km}$

Step 3: Calculate total distance covered from Monday to Friday

Total distance = (Distance covered on Mon, Wed, Fri) + (Distance covered on Tue, Thu)

$\text{Total distance}=11.175 \mathrm{km}+4.018 \mathrm{km}=15.193 \mathrm{km}$

Hence, the total distance covered by Radha from Monday to Friday is 15.193 km.